Overconfidence is a disadvantage in war, finds study

Overconfident people are more likely to wage war but fare worse in the ensuing battles, a new study suggests. The research on how people approach a computer war game backs up a theory that "positive illusions" may contribute to costly conflicts.

"It supplies critically needed experimental support for the idea that positive attitude - which is generally a [beneficial] feature of human behaviour - may lead to overconfidence and [damaging] behaviour in the case of war," comments Peter Turchin of the University of Connecticut, US.

Previous work has suggested that mentally healthy people can have highly optimistic predictions, or "positive illusions". This optimism may have offered an evolutionary advantage in the past, allowing our ancestors to cope with adversity and bluff opponents.

But in the present day this optimism may wreak havoc on international relations, argue the researchers, who conducted computer simulations to test their hypothesis.

Conflict diamonds

Dominic Johnson of Princeton University in New Jersey and his colleagues recruited 200 volunteers to play the role of the leader of a fictitious country that is in conflict with another over newly discovered diamond resources that lay along a disputed border.

Before the game, volunteers were asked to predict how their performance would rank compared with the other 199 people in the experiment. They then played anonymously against other volunteers and received $10 if they won the game, that is, if they amassed the most wealth or defeated their opponent in war.

Each player began with $100 million in game money to invest in their military or industrial infrastructure, or to reserve as cash. The program gave them constant updates about the offers and actions of their opponents.

Careful negotiations with opponents could win players additional resources in exchange for the diamonds. But they also had the option of waging war. Their victory in battle was determined by how much they had invested in their military, along with an element of chance.

The harder they come

Players who made higher-than-average predictions of their performance - those who had higher confidence - were more likely to carry out unprovoked attacks. These warmongers ranked themselves on average at number 60 out of the 200 players, while those who avoided war averaged out at the 75 position.

A further analysis showed that people with higher self-rankings ended up worse off at the end of the game. "Those who expected to do best tended to do worst," the researchers say. "This suggests that positive illusions were not only misguided but actually may have been detrimental to performance in this scenario."

Men tended to be more overconfident than women. But the study found nothing to back up the popular idea that high testosterone causes confidence and aggression. Saliva tests showed that, within each gender group, testosterone level did not correlate with how participants expected to perform in the game.

Those who launched unprovoked attacks also exhibited more narcissism, scoring 13 out of 15 on a standard psychological test. More peaceful types scored 11 on average on the same test. The trend applied to both men and women. "So it's not maleness per se but narcissism that makes some people overly optimistic and aggressive," suggests Bertram Malle at the University of Oregon in Eugene, US.

Overconfident administration

"This study fits within a relatively new field of research which connects motivations of individual people to their collective behaviour," says Turchin.

"One wishes that members of the Bush administration had known about this research before they initiated invasion of Iraq three years ago," he adds. "I think it would be fair to say that the general opinion of political scientists is that the Bush administration was overconfident of victory, and that the Iraq war is a debacle."

Malle agrees that the study raises worrying questions about real-world political leaders. "Perhaps most disconcerting is that today's leaders are above-average in narcissism," he notes, referring to an analysis of 377 leaders published in King of the Mountain: The nature of political leadership by Arnold Ludwig.

Journal reference: Proceedings of the Royal Society B (DOI: 10.1098/rspb.2006.3606)

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